title: [Influence factors on the formation of mammospheres from breast cancer stem cells].
abstract: OBJECTIVE
  To investigate the influential factors on the formation of mammospheres from MCF-7, MDA-MB-231 and primary breast cancer epithelial cells, and to detect the proportion of CD44+/CD24(-/low) among them.
  
  
  METHODS
  MCF- 7, MDA-MB-231 and primary breast cancer epithelial cells were cultured in suspension to generate primary mammospheres. After 7 days of cultivation, the proportion of cancer stem cells was measured in cells derived from mammosphere cells or monolayer culture cells by flow cytometry.
  
  
  RESULTS
  MCF-7 had the highest efficiency of mammosphere formation (2.1%+/-0.3%), while MDA-MB-231 cells hardly had any mammosphere formation, and no mammosphere formation was observed in breast cancer epithelial cells. MCF-7 tended to adhere under stem cell culture conditions without B27. Flow cytometry analysis indicated that, compared with 2.0%+/-0.1% for the MCF-7 monolayer culture cells, 11.8%+/-0.3% and 8.2%+/-0.8% of the MCF-7 mammosphere cells from MCF-7 under different conditions were CD44+/CD24(-/low) (P < 0.01). The proportion of CD44+/CD24(-/low) expression in MDA-MB-231 cells and primary breast cancer epithelial cells was 92.2%+/-3.1% and 93.8%+/-2.4%, respectively.
  
  
  CONCLUSIONS
  Compared with monolayer culture cells, MCF-7 mammosphere cells contained higher proportion of breast cancer stem cells, while MDA-MB-231 and primary breast cancer epithelial cells did not. The expression of CD44+/CD24(-/low) in MDA-MB-231 and primary breast cancer epithelial cells did not correlate with mammosphere formation positively.
authors.affiliation: Department of Oncology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200127, China.
authors.forename: Ming-zhu
authors.initials: MZ
authors.lastname: Huang
authors.forename: Feng-chun
authors.initials: FC
authors.lastname: Zhang
authors.forename: Yan-yun
authors.initials: YY
authors.lastname: Zhang
mesh_terms: D001943:Breast Neoplasms / Q000473:pathology*; D051927:CD24 Antigen / Q000378:metabolism; D045744:Cell Line, Tumor; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism; D014411:Neoplastic Stem Cells / Q000378:metabolism* / Q000473:pathology; D018874:Spheroids, Cellular / Q000166:cytology* / Q000378:metabolism*
chemical_list: D051927:CD24 Antigen; D018960:Hyaluronan Receptors